Field of the Invention
The present invention relates to motorcycle tyres. In particular, the present invention relates to tyres intended to be mounted on the front wheel of motorcycles of the “Supersport” and/or “Sport Touring” segment, having large engine capacity (e.g. 600 cm3 or higher), and/or high power (e.g. 170-180 hp or higher), also used on tracks.
Description of the Related Art
In recent times a trend has been observed to introduce in the market motorcycles for Supersport or Sport Touring use having high power. For example, motorcycles for road use having an engine capacity of 1000 cm3 or higher, with powers of 180 hp, are in fact already available on the market.
For ensuring such high performances, the tyres mounted on the wheels of such motorcycles shall have excellent features as regards the grip to the ground, so as to be able to effectively transfer the high traction torque to the ground, both in straight running and while accelerating on leaving a bend, as well as ensure an effective braking action. The grip becomes a really critical issue above all when running on wet road surfaces.
For ensuring to the motorcyclist that such performances are reached in a fully safe condition, the tyres shall ensure, together with a very good grip to the ground, behaviour stability both in straight running and while running on bends, particularly in conditions of high acceleration/deceleration. In fact, a stable behaviour of the tyre indicates its capacity to effectively dampen perturbations transmitted by the unevenness of the road surface while running, so that such perturbations are not propagated to the motorcycle, thus compromising the driving stability.
Patent application EP 1826026 describes a tyre for motorcycles, especially adapted to be used as a front tyre of a racing motorcycle, comprising a tread portion provided with at least one pair of circumferential grooves extending generally in a circumferential direction of the tyre and oppositely disposed relative to the equatorial plane of the tyre, and a plurality of grooves inclined with respect to the circumferential direction and extending from an outer side to an inner side in a width direction on the tread band. At least half of the inclined grooves extend across the equatorial plane of the tyre. According to EP 1826026, this choice allows a tyre with extremely light handling and stable when braking to be obtained.
FIGS. 1a and 1b show tread pattern portions respectively of the front and rear Sportec™ M3 tyres. The Sportec™ M3 tyres, presently marketed by Metzeler™, are very much appreciated by motorcyclist keen on the Supersport segment.